Enameling metal



Patented Mar. 5, 19 29. I

warren STATES PATENT OFFICE.- I

wnsmv :r. nncx AND nuns mnurrnam, or mnnrn'rown, onro, ASSIGNOBS 'ro run AMERICAN ROLLING m1. comm, or mmnmrown, orrro, A consonathe same timefbeing formablein dies and by taken to prevent excessive piping,

TION OF OHIO.

R0 Drawing.

to enameling, firm adherence of enameled coating, absence of bubbles, or-unevenness in surface of vitreous enameled coatings.

The importance of our invention includes among other things the possibility of control of its production to the end of producin 'a.

uniform product, and our object genera y stated is to produce a deep drawing steel which will take smoothly and hold permanentlya coating of enamel, particularly vitreous enamel.

The appl'ication of vitreous enamel is attended by raising the temperature of a piece of metal coated with enamel to a temperature of around 1600 degrees Fahrenheit, and our steel withstands this temperature, while at spinning into various-objects while'cold, and prior to being enameled.

We have-also discovered that this steel has the property of box annealing at a much lower temperature, than other types of steel used for similar-purposes, and, therefore, the

a on account of any under anne material. is not so likelyto prove defective a ing which may be imparted thereto. j

Our new steel is of the e known as killed steel, and contains sihcon in greater quantities than an deep drawing and spinning steel with w ich we are famillar. In fact the silicon content is as high as steel used for casting purposes, while the other ingredi- ENAMELING METAL.

Applicatlon' flled November, 18, 1928. Serial 1T0. 675,208.

outs in the steel are within'the mild steel range. I

As a typical analysis for a steel which we have found to give excellent results as above outlined, we give the following:

I Per cent.

Silicon Sulphur Carbon 7 .08- Manganese .40 Copperv .04

The silicon is added to the material after it has been refined to the range of mild steel, and kills the steel, by which we mean it revents the evolution of the ases contained therein in the ingot mold. ince killing of a,steel with silicon in an amount as high as around .15 percent will result in a piped ingot unless something is done, to prevent excessive pipe, we recommend that care be if the best economy in production'is desired.

Phosphorus .015

So far as we are'advised it has been the practice and teaching in the metallurgical art that steel for the purposes outlined, shouldbe free from silicon, and it should be noted, that in our steel we have radically departed from this practice, producing a mild steel and deliberately increasing the silicon content.

The typical analysis which we have given is intended as a guide and not as a limitation of our invention, and indicates a regular mild steel product such as is produced in the open hearth or other metallurgical refinement process.

It is probable that the silicon present in X the sheet is some way united with the enamel in the vitreous enameling process, giving the enamel a firm anchorage or bond with the jectives of our product.

Having thus described our invention, what we claim as new and desire to secure by Letters Patent, is

1. A vitreous enameled article formed of steel, which except for silicon comes within the mild steel range, and has in addition a quantity of silicon sufiicient to give a bond 2 with enamel, when put through an enamelspinning qualities, which is one of the main ing process, but not suflicient to spoil the deep drawing and spinning property in the steel prior to enameling.

2. A vitreous enameled article formed of steel, which contains below one tenth of one 25 precent of carbon and in excess of one tenth of one percent of silicon.

3. A vitreous enameled article formed of steel, which contains below one tenth of one WESLEY J. BECK. JAMES -A. AUPPERLE; 

